Chef
Configuration management tool which uses a pure-Ruby, domain-specific language (DSL) for writing system configuration recipes. Supports Linux, UNIX, Windows, and AIX as first-class citizens for management.
linux windows open-source provisioning config-mgmt ruby
FastForward
Flexible operating-system event and metric forwarding agent. Receives input and forwards output using plugins.
linux windows osx open-source metrics monitoring ruby
Orc
A model driven orchestration tool for deployment of application clusters
linux windows osx open-source provisioning orchestration ruby
Rex
A agent-less server orchestration tool built on Perl
linux windows osx open-source orchestration perl
Soloist
Soloist lets you quickly and easily converge Chef recipes using chef-solo.
linux windows osx open-source provisioning ruby
Vagrant
Vagrant is a cross platform tool to create, boot, configure and destroy development environments. It provides a simple configuration-based approach to take a base image, boot it up, provision it (using any other provisioners), SSH, port forward, and much more. It automates the process of booting up and configuring virtual machines. It supports various providers like VirtualBox, VMWare, AWS, LXC, etc.
linux windows osx open-source virt provisioning ruby